Beatrice Vasey
    Free garden tool

    South West frost date finder

    Enter your postcode to see when the last spring frost and first autumn frost usually fall where you garden in Cornwall, the Isles of Scilly, Devon, Somerset, Dorset, Wiltshire, Gloucestershire and Bristol, worked out from 30 years of Met Office records for your square kilometre. Use it to decide when to sow, when it's safe to plant out, and when to bring tender plants in.

    Last frost dates across the South West

    Frost dates change a lot over short distances. The typical last frost in Cirencester is 55 days later than in Newquay, so a planting date that suits Newquay can lose plants in Cirencester.

    Map of the South West shaded by typical last spring frost date for each square kilometre.
    Bristol
    Exeter
    Plymouth
    Penzance
    Cheltenham
    Yeovil
    Barnstaple

    Typical last spring frost

    • By 31 March
    • 1 to 15 April
    • 16 to 30 April
    • 1 to 15 May
    • After 15 May
    • Outside the South West
    Each square is 1 km. Hover over the map to see the dates for any square. Contains Met Office data © Crown copyright. Region boundaries: Office for National Statistics, Open Government Licence; contains OS data © Crown copyright and database right 2023.
    TownTypical last frostSafe to plant outTypical first autumn frostFrost-free days
    Newquay23 February30 March22 December302
    Penzance24 February6 April27 December306
    Torquay26 February2 April19 December296
    Weymouth3 March23 March13 December285
    Minehead6 March5 April16 December285
    Plymouth8 March9 April3 December270
    Weston-super-Mare14 March7 April29 November260
    Truro21 March16 April24 November248
    Bodmin25 March13 April3 December253
    Bristol25 March19 April12 November232
    Tiverton3 April19 April17 November228
    Barnstaple5 April21 April17 November226
    Gloucester5 April19 April10 November219
    Exeter6 April27 April13 November221
    Bath7 April21 April14 November221
    Wells7 April27 April12 November219
    Bournemouth7 April28 April12 November219
    Okehampton11 April21 April17 November220
    Cheltenham11 April28 April7 November210
    Launceston12 April12 May14 November216
    Swindon13 April27 April7 November208
    Dorchester14 April1 May9 November209
    Princetown16 April6 May13 November211
    Taunton16 April30 April15 November213
    Yeovil16 April11 May4 November202
    Salisbury16 April11 May5 November203
    Cirencester19 April12 May4 November199

    Figures for the square kilometre at each town centre, 1991 to 2020. Contains Met Office data © Crown copyright.

    How to use your frost dates

    Hardy seeds outsideSow broad beans, peas, carrots and other hardy crops from around your typical last frost date, once the soil has warmed.
    Tender plants indoorsStart tomatoes, peppers and squash indoors six to eight weeks before your safe-to-plant-out date.
    Hardening offPut young plants out during the day for a week or two before your safe date, and bring them in at night.
    Planting outPlant tender crops and bedding after your safe date, and keep fleece handy for a late cold snap.
    AutumnLift dahlias, bring in tender pots and pick the last tomatoes before your 1-in-10 early frost date.

    Not sure what will cope with your frost dates? I'm a horticulturist trained at the Royal Botanic Garden Edinburgh, and I draw planting plans for gardens anywhere in the UK, choosing plants for your soil, your light and the frosts you get.

    Frost dates in other regions

    RegionEarliest last frostLatest last frost
    North East22 March in Whitley Bay21 May in Kielder
    North West17 March in Liverpool17 May in Alston
    Yorkshire and the Humber3 March in Scarborough8 May in Hawes
    East Midlands24 March in Skegness25 April in Buxton
    West Midlands10 April in Coventry25 April in Ludlow
    East of England11 March in Cromer4 May in Thetford
    London1 March in Westminster14 April in Orpington
    South East22 February in Margate5 May in Dorking
    South West23 February in Newquay19 April in Cirencester

    Frost date questions

    When is it safe to plant out in the South West?

    It depends on where you are. In Weymouth, tender plants are usually safe from 23 March, but in Cirencester you need to wait until 12 May. Put your postcode into the finder above and use the "safe to plant out" date, which only 1 year in 10 beats.

    Why are these dates different from the ones on seed packets?

    Seed packets and national charts give one date for the whole country, but frost dates can differ by weeks between the coast, towns, valleys and higher ground. These dates come from frost records for your own square kilometre.

    What's the difference between an air frost and a ground frost?

    An air frost is when the air at 1.5 m drops below 0°C, which is what these dates measure. A ground frost forms on grass and soil, and on clear, still nights it can happen when the air is still a degree or two above freezing. Low-growing seedlings feel ground frosts first, so give them an extra week or two of protection.

    Where does the data come from?

    The dates are worked out from the Met Office's HadUK-Grid daily minimum temperatures on a 1 km grid for 1991 to 2020, the standard 30-year climate period. For every square kilometre, we found the last night below freezing each spring and the first each autumn, then took the typical date and the 1-in-10 late date across the 30 years. We checked the results against the Met Office's own weather station records.

    Does the finder work outside the South West?

    Yes. It works for any postcode in England, and the frost map of England compares every region.

    Can I use these figures in an article, newsletter or allotment notice?

    Yes. Please credit Beatrice Vasey and link to this page, and include "Contains Met Office data © Crown copyright" for the underlying records.

    Sources (6)